As for this summer so far, Mr Ray said: "Temperatures have been quite spikey and we have seen slightly above average numbers of hot days this summer. But [overall] it has been a little bit cooler and milder than this time last year."

Future rain events

Mr Ray said the IOD also influenced the noticeable increase in severe, localised storm activity.

"We saw that reflected in a really high number of intense low pressure systems and cold fronts producing conditions that were windier than usual," he said.

Mr Ray said direct observational evidence from satellite weather stations showed an increase in greenhouse gases in the atmosphere.

As a result, in the future, the tropics zone will broaden and provide less frequent but heavier rain events for Adelaide.

"Things will continue to get warmer, with more temperature extremes," Mr Ray said.

"When we do get significant rainfall, it will come more intensely and we are starting to see some indications of that being the case."